In Jannah (Paradise) there is a gate called Ar-Raiyan

“In Jannah there is a gate which is called Ar-Raiyan through which only those who observe Saum (fasting) will enter on the Day of Resurrection. None else will enter through it.

It will be called out, “Where are those who observe fasting?” So they will stand up and proceed towards it. When the last of them will have entered, the gate will be closed and then no one will enter through that gate.”